A big year for Junichi Tazawa

Junichi Tazawa, who pitched a scoreless inning today in his first spring training appearance, almost certainly is destined for Triple-A Pawtucket when the Red Sox head north. Tazawa got his first taste of the major leagues last season, compiling a 7.46 ERA in six appearances and, most memorably, surrendering a walk-off home run to Alex Rodriguez in the 14th inning of an epic game in early August.

Everything that happened last season was about gaining experience -- and every pitch thrown in the major leagues was a bonus.

"I don't know if I would have sat here and said, 'We'll see him pitching in the big leagues,'" Red Sox manager Terry Francona said. "Helping our ballclub, that was a lot to ask last year."

Here's the only problem: Tazawa isn't 20 years old. He's not 21, either. He turned 23 midway through last season, and that's the age at which many young pitchers start to blossom. There were 25 players who threw at least as many major-league innings as he did at the age of 22 or younger. Eight of those pitchers, including emerging stars Brett Anderson, Tommy Hanson, Derek Holland and Rick Porcello, threw more than 100 major-league innings.

Other names on the list include Neftali Feliz, Brian Matusz, Jon Niese and Chris Tillman, all pitchers expected to make a significant impact on their respective teams this season at the age of 22 or 23. Heck, Tazawa is three months older than Michael Bowden, the longtime prospect on whom it seems many are ready to give up.

Tazawa will turn 24 in mid-June, and that means the clock is starting to tick a little bit. Prospects who haven't made an impact in the major leagues by the time they're 25 tend not to be considered prospects anymore. Josh Beckett was 23 when he struck out 150 hitters for the first time. Jon Lester was 23 when he won a World Series clincher. John Lackey was, too.

Tazawa, of course, doesn't have the same type of ceiling as Beckett, Lackey or Lester. But even if you look at him as a back-of-the-rotation swingman in the mold of Justin Masterson, well, Masterson was pitching key innings in the postseason at 23 and taking the place of Tim Wakefield in the starting rotation at 24.

The righty remains an intriguing possibility for the Red Sox either as a starter or a reliever. He'll open the season at Triple-A Pawtucket and will have a chance to keep piling up innings and to keep working on his pitches. He'll certainly be in the mix should the Red Sox run into any depth issues with their pitching staff -- but it'll take either a significant injury or a significant step forward in his development for him to make a significant impact at the major-league level.

Like Bowden, if he's going to deliver on his big promise, his window isn't going to stay open forever.